This disclosure relates to a sample chamber for containing a biomaterial.
In FIG. 1 of U.S. Pat. No. 7,846,715 (the '715 patent) a sample chamber 100 is disclosed which allows various types of tissues and other types of biomaterials to be conditioned. The contents of the '715 patent are incorporated herein by reference. A user-defined conditioning profile specifies a desired mechanical stimulation of a sample. To allow for the introduction of fluids (or other content), the sample chamber 100 is sealed to define a chamber volume 102 within which a specimen 104 is positioned. The sample chamber 100 includes two push rods 106, 108 that allow the specimen 104 to be held along an axis. Along with assisting with mechanical stimulation, the orientation and position of the push rods 106, 108 may be manually changed for adjusting the specimen.
The sample chamber 100 also includes a chamber window 114 that allows the chamber volume 102 and the specimen 104 to be viewed during conditioning. Various types of transparent material (e.g., plastics, glass, etc.) may be used to produce the window 114 while still providing the appropriate structural integrity needed for conditioning with the sample chamber 100. The window 114 is secured against a compliant element (e.g. an O-ring) with six fasteners (see FIGS. 4b and 5) in order to provide a leak-proof seal between the chamber 100 and the window 114. These fasteners (e.g. screws) apply compression around the perimeter of the sealing area. If there isn't enough compression all along the element, the seal will leak. The number and placement of the fasteners is determined by the pressure and stiffness of the elements involved.
As the fasteners and a tool used to adjust the fasteners (e.g. a hex key) are not typically attached to the chamber, they can become lost. In addition, having to tighten a number of fasteners increases the time it takes to assemble the chamber. The samples used in the chamber often contain living cells that are very sensitive to environmental changes (e.g. exposure to air flow can kill them). As such, all interactions with the chamber take place in controlled environments with filtered air. The temperature is also critical. If the cells are allowed to get too cold or too hot, they will die. This temperature window is relatively small (e.g. around 2° C.). The speed with which cellular samples can be installed in the chamber minimizes the biological stress they experience. Thus securing and sealing the chamber quickly is very advantageous. Further, the use of fasteners and related tools can introduce contamination into the chamber in which case samples will need to be discarded. It also takes additional time to clean and sterilize the fasteners and tools.